1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
---
title: "jq is a powerful JSON processor"
date: 2021-06-13
categories: [ blog, software ]
tags: [unix, jq, json, cli, guide, tinker]
---
So lately I've been using `jq` quite a bit. It is a CLI JSON processor that
makes your life easier if you have to deal with a lot of JSON. Here I'm going
to give two examples of how it's used.
## Search response
I've been dealing with JSON from Elasticsearch API[^0], but as they would not
release their documents under a free license, I will take an example from
OpenSearch instead[^1]:
```json
{
"took": 39,
"timed_out": false,
"_shards": {
"total": 68,
"successful": 68,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 5837,
"relation": "eq"
},
"max_score": 7.8623476,
"hits": [
{
"_index": "new_shakespeare",
"_type": "_doc",
"_id": "100763",
"_score": 7.8623476,
"_source": {
"type": "line",
"line_id": 100764,
"play_name": "Troilus and Cressida",
"speech_number": 43,
"line_number": "3.1.68",
"speaker": "PANDARUS",
"text_entry": "Sweet queen, sweet queen! thats a sweet queen, i faith."
}
},
{
"_index": "shakespeare",
"_type": "_doc",
"_id": "28559",
"_score": 5.8923807,
"_source": {
"type": "line",
"line_id": 28560,
"play_name": "Cymbeline",
"speech_number": 20,
"line_number": "1.1.81",
"speaker": "QUEEN",
"text_entry": "No, be assured you shall not find me, daughter,"
}
}
]
}
}
```
Woah that's long!
How do you know how much time it took? I want to measure the performance.
```sh
$ curl ... | jq '.took'
39
```
Nice. Not very helpful, though---I can easily see that at the top of the
result. I want to see which responses were returned.
```sh
$ curl ... | jq '.hits.hits'
[
{
"_index": "new_shakespeare",
"_type": "_doc",
"_id": "100763",
"_score": 7.8623476,
"_source": {
"type": "line",
"line_id": 100764,
"play_name": "Troilus and Cressida",
"speech_number": 43,
"line_number": "3.1.68",
"speaker": "PANDARUS",
"text_entry": "Sweet queen, sweet queen! thats a sweet queen, i faith."
}
},
{
"_index": "shakespeare",
"_type": "_doc",
"_id": "28559",
"_score": 5.8923807,
"_source": {
"type": "line",
"line_id": 28560,
"play_name": "Cymbeline",
"speech_number": 20,
"line_number": "1.1.81",
"speaker": "QUEEN",
"text_entry": "No, be assured you shall not find me, daughter,"
}
}
]
```
The response is the value of `hits` inside a `hits`, so the query is
`.hits.hits`. How intuitive!
But this is hard to read. Let's just take the `play_name` of the result.
```sh
$ curl ... | jq .hits.hits[]._source.play_name
"Troilus and Cressida"
"Cymbeline"
```
Neat! But how does it work? The brackets `[]` signifies that we should take
all the results, from each of which the value for `._source.play_name` is
taken.
There might be the option to write that in the search query DSL, which also
reduces the data transferred, but I bet this is much easier to write.
## Wallpaper
I use `feh` for setting wallpaper, which can take an image from the internet.
Previously, I used a static list that I collected myself, but I recently
discovered a wallpaper API from [wallhaven](https://wallhaven.cc/help/api).
Let's say, I want to get a space image as wallpaper, I would use this command:
```sh
curl -s 'https://wallhaven.cc/api/v1/search?q=space&ratios=16x9&sorting=toplist'
```
Where `q` is the query, `ratios` is the image ratio so that it fits the screen,
and `sorting` is the way the results would be sorted before pagination. The
results is long, but it looks like this:
```json
{
"data": [
{
"id": "l3zmwy",
"url": "https://wallhaven.cc/w/l3zmwy",
"short_url": "https://whvn.cc/l3zmwy",
"views": 67050,
"favorites": 705,
"source": "https://www.artstation.com/artwork/YaQwgP",
"purity": "sfw",
"category": "general",
"dimension_x": 1920,
"dimension_y": 1080,
"resolution": "1920x1080",
"ratio": "1.78",
"file_size": 781731,
"file_type": "image/jpeg",
"created_at": "2021-05-18 19:26:23",
"colors": [
"#424153",
"#000000",
"#663300",
"#996633",
"#999999"
],
"path": "https://w.wallhaven.cc/full/l3/wallhaven-l3zmwy.jpg",
"thumbs": {
"large": "https://th.wallhaven.cc/lg/l3/l3zmwy.jpg",
"original": "https://th.wallhaven.cc/orig/l3/l3zmwy.jpg",
"small": "https://th.wallhaven.cc/small/l3/l3zmwy.jpg"
}
},
...
]
}
```
So, to get the image path from this, I run:
```sh
curl ... | jq -r .data[].path | shuf -n 1 | feh --bg-center
```
I use `shuf` because I'd like a new wallpaper every time I run this script.
Put this as the startup script or add a cron job and you'll have a changing
wallpaper. Disclaimer: this script does not always work, because of `feh`.
If you're using GNOME, for example, `feh` can't be used to set background.
[^0]: Yes I know it's no longer free software (it still partially is I think).
I have no choice, and I would still be more at peace with a source available
software that is self-hostable.
[^1]: Copyright 2021 OpenSearch contributors. Released under Apache License.
|
